1. The plaintiffs are purchasers of the whole or part of the equity of redemption in certain properties. They executed a mortgage for a period of 9 years to one Karuppa Udayan which authorised him to redeem an alleged prior mortgage in favour of the family of defendants Nos. 1 to 7. He obtained a decree for redemption against that family but failed to execute it. The plaintiffs were also impleaded as defendants in that suit (0.S. No. 388 of 1906) as persons having an interest in the mortgaged property. The plaintiff subsequently paid off Karuppa Oodayans mortgage. They now seek to redeem the mortgage in the defendants favour. The original mortgage deed has not been produced by the defendants, but. the plaintiffs have put in Ex 1 a registration copy of it. The defendants denied the mortgage set up by the plaintiffs and contended that they were themselves the owners of the property. An issue was therefore framed in these terms" whether the plaint mentioned mortgage is true." Both the lower Courts have held it proved. Two contentions have been argued in second appeal. First that the mortgage is invalid in law because it was not attested by two witnesses but only by one witness